lancaster



Du h S w e e h S 2 R E T S A G N A L H (No Model.)

cLAM SHELL S0001? 0R DIGGING APPARATUS.

Patented Jan. 18, 1898.

wwweoozo (No Model.) 2 Sheets-Sheet 2. J. H. LANCASTER. ULAM SHELL $0001 0R DIGGING APPARATUS.

No. 597,422. Patented Jan. 18.1898.

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UNITED STATES PATENT @rrich.

JAMES H. LANCASTER, OF NEWV YORK, N. Y.

CLAM-SHELL SCOOP OR DIGGING APPARATUS.

SPECIFICATION formingpart of Letters Patent No. 597,422, dated January 18, 1898.

Application filed July 3, 1898. Serial No. 479,447. (No model.)

' To (LZZ 2071,0711, it may concern.-

ging Apparatus, of which the following is a ,full, clear, and exact specification.

The present invention has reference to clamshell dredges, buckets, or digging apparatus; and it consists in. the improved construction hereinafter described, whereby a dredge grappie, bucket, or dipper is produced which shall not only be of more durable and simple character than previous types, but which will be more positive in operation.

The invention further con-tern plates provision that will limit the opening of the scoop or tooth sections and relieve the parts of undue strain or thrust, thereby preventing the connections from becoming jammed.

In the drawings forming part of this specification, Figure 1 is a perspective view of a clam-shell dredge or bucket embodying my improvements. Fig. 2 is a side elevation of the same partly broken away and showing by full and dotted lines the position of the parts when the bucket is both in a closed and open position. Fig. 3 is an end elevation of the improved bucket or dredge. Fig. 4: is a top plan view of the same.

The ends of the bar or shaft A are reduced to present the cylindrical bearings a, on which are hung the eyes 17 I), carried by straps secured to the scoop-sections B B, said eyes being bent slightly out of horizontal alinement in order that they will hang in companion pairs on the bearing ends a, and thus the adjacent edges of the scoop-sections will register and practically form a water-tight bucket.

To the outer edge portion of each scoop-section B are bolted a pair of ears 0 a, each transversely perforated for the reception of apivotbolt (3, which also engages the bit u rcated ends 6 of an outwardly-inclined bar 0, the upper perforated end of which movably engages a lug f, projecting from the end of a cross-head D. It will be noted that each pairof end bars 0 depends and issuspended from the same pivot-lug f.

'lhe cross-head D has central recess enlarged at a certain point to admit of the location of a groove-roller the journals h of which bear in the vertical sides of the crosshead.

On the pivot-shaft A are shrunk rings '6, serving to clamp in position a pair of bellcrank levers E F, which are mounted on such shaft at their elbows.

' As will be noted from the several figures of the drawings, the horizontal member j of each bell-crank lever carries a flattened head In at its outer extremity, which bears on the inner face of the adjacent scoop-section B at about the center thereof and is bolted thereto.

The vertical membcrZ of each bell-crank lever terminates at its upper free end in an eye or, which is embraced by the lower bifurcated end it of a depending link G, said bifurcated end being perforated for the passage of a bolt to secure its pivotal attachment to the eye of the vertical member I. It will be noted that the vertical members Z normally slightly diverge toward their upper ends, while the links G converge toward their upper ends, at which point they are respectively secured between bea-ring-ears 0, carried by apulley-casting H and pierced by a pivot-bolt p. The said pulley-castingis of the form most clearly shown in Fig. 2, and, besides the lower horizontal portion, forming the earo, also includes a vertical pairof ears q, in which is journaled a grooved pulley I, around which passes a chain 0, one end of which is permanently at: tached in the recess of the head D, while the rest of the chain is in operative connection with the hoisting-drum or other equivalent mechanism. Short lengths s of chain are mutually attached for the connection of a second hoisting-chain, it being intended to first'exert traction on the chain r to close the scoop-sections through the medium of the mon bearin-gt'. e. the shaft A-which in turn also serves as a common bearing or journal for each pair of end eyes of the scoop-sections B. Such an arrangement is not only simple, but it enables the employment of a o0mpara tively small number of parts and at the same time insures the positive operation of the scoop-sections.

As will be readily apparent, if the pulleycasting II is lowered to an extent that it would wedge in between the links G or reach a deadcenter with respect to the same then the parts are sure to experience an undue strain or thrust. To avoid such a result, I provide said pulley-casting H with a depending extension u, designed to contact with or between the pinch of the vertical members Z of the bellcrank levers E and F, and thus limit and brace the scoop-sections against an excessive opening.

It will be obvious that the improvements previously explained with reference to clamshell buckets or dredges are susceptible of application to the constructionof grapples generally. Thus, for instance, in lieu of the scoop-sections B outer horizontal bars or segment portions may be pivotally hung by arms upon the shaft A, said bars or segments being provided with depending tines or teeth, removable or otherwise.

I claim 1. In a dredge, bucket or digging device, the combination with the main shaft A, of scoop or digging sections pivotally hung thereon at their inner upper angles, a cross head, bars movably depending therefrom and pivotally connected to the outer portions of the sections together with bell-crank levers mounted at their elbows on the shaft A, and having their horizontal members secured to the outer portions of said sections and their vertical members to operating means for vibrating them, substantially as set forth.

2. In a dredge, bucket or digging device, the combination with the main shaft A, of scoop or digging sections pivotally hung thereon at their inner upper angles, a crosshead, bars movably depending therefrom and pivotally connected to the outer portions or the sections, together with bell-crank levers mounted at their elbows on the shaft A, and having their horizontal members secured to the outer portions of said sections and their vertical members by links to a chain-operated casting, substantially as set forth.

In adredge, dipper or digging apparatus of the character described, the combination with the scoop or digging sections pivotally suspended on the same shaft A, bell-crank levers for operating the said scoop-sections, also pivotally mounted on said shaft, a casting II, connected by links to the vertical members of said bell-crank levers, and having a lower extension 14, for limiting the descent of said casting and the opening of the scoopsections, substantially as set forth.

4. In a dredge, bucket or digging apparatus. the combination with scoop or digging sections both pivotally hung on the same shaft A, and connected to the scoop or digging sections for operating the same, a recessed crosshead, suspending bars depending from the latter and connected to said scoop-sections at their outer edges, a casting II, connected by links to the vertical members of bell-crank levers and carrying a pulley, a chain connected to the cross-head and passing around said pulley through the recess of said head, substantially as set forth.

In testimony that I claim the foregoing I have hereunto set my hand this 30th day of J une, 1893.

JAMES H. LANCASTER.

\Vitnesses WILLIAM PAXTON, HERBERT IV. E. IIANNAM. 

